Laxatives

Laxatives are a type of medicine that help you pass stools. There are several different types of laxative and each one has a different effect on your digestive system.

Bulk-forming laxatives

Your GP will usually start you on a bulk-forming laxative. These work by helping your stools to retain fluid. This means they're less likely to dry out, which can lead to faecal impaction. Bulk-forming laxatives also make your stools softer, which means they should be easier to pass.

Commonly prescribed bulk-forming laxatives include ispaghula husk, methylcellulose and sterculia. When taking this type of laxative, you must drink plenty of fluids, and don't take them before going to bed. It will usually be two to three days before you feel the effects of a bulk-forming laxative.

Osmotic laxatives

If your stools remain hard after you've taken a bulk-forming laxative, your GP may prescribe an osmotic laxative instead. Osmotic laxatives increase the amount of fluid in your bowels. This softens your stools and stimulates your body to pass them.

Commonly prescribed osmotic laxatives include lactulose and macrogols. As with bulk-forming laxatives, make sure you drink enough fluids. It will usually be two to three days before you feel the effect of the laxative.

Stimulant laxatives

If your stools are soft, but you still have difficulty passing them, your GP may prescribe a stimulant laxative. This type of laxative stimulates the muscles that line your digestive tract, helping them to move stools and waste products along your large intestine to your anus.

The most commonly prescribed stimulant laxatives are senna, bisacodyl and sodium picosulphate. These laxatives are usually only used on a short-term basis, and they start to work within 6 to 12 hours.

According to your individual preference and how quickly you need relief, your GP may decide to combine different laxatives.

How long will I need to take laxatives for?

If you've had constipation for a short time, your GP will usually advise you to stop taking the laxative once your stools are soft and easily passed.

However, if your constipation is caused by an underlying medical condition or a medicine you're taking, you may have to take laxatives for much longer, possibly many months or even years.

If you've been taking laxatives for some time, you may have to gradually reduce your dose, rather than coming off them straight away. If you have been prescribed a combination of laxatives, you'll normally have to reduce the dosage of each laxative, one at a time, before you can stop taking them. This can take several months.

Your GP will advise you about when it's best to stop taking laxatives.

Treating faecal impaction

Faecal impaction occurs when stools become hard and dry and collect in your rectum. This obstructs the rectum, making it more difficult for stools to pass along.

Sometimes as a result of impaction, overflow diarrhoea may occur (where loose stools leak around the obstruction). You may have difficulty controlling this.

If you have faecal impaction, you'll initially be treated with a high dose of the osmotic laxative macrogol. After a few days of using macrogol, you may also have to start taking a stimulant laxative.

If you don't respond to these laxatives, and/or if you have overflow diarrhoea, you may need one of the medications described below.

Suppository – this type of medicine is inserted into your anus. The suppository gradually dissolves at body temperature and is then absorbed into your bloodstream. Bisacodyl is an example of a medication that can be given in suppository form.

Mini enema – where a medicine in fluid form is injected through your anus and into your large bowel. Docusate and sodium citrate can be given in this way.

Pregnancy or breastfeeding

If you're pregnant, there are ways for you to safely treat constipation without harming you or your baby. Your GP will first advise you to change your diet by increasing fibre and fluid intake. You'll also be advised to do gentle exercise.

If dietary and lifestyle changes don't work, you may be prescribed a laxative to help you pass stools more regularly.

Lots of laxatives are safe for pregnant women to use because most aren't absorbed by the digestive system. This means that your baby won't feel the effects of the laxative.

Laxatives that are safe to use during pregnancy include the osmotic laxatives lactulose and macrogols. If these don't work, your GP may recommend taking a small dose of bisacodyl or senna (stimulant laxatives).

However, senna may not be suitable if you're in your third trimester of pregnancy, because it's partially absorbed by your digestive system.

Babies who haven't been weaned

If your baby is constipated but hasn't started to eat solid foods, the first way to treat them is to give them extra water between their normal feeds. If you're using formula milk, make the formula as directed by the manufacturer and don't dilute the mixture.

You may want to try gently moving your baby's legs in a bicycling motion or carefully massaging their tummy to help stimulate their bowels.

Babies who are eating solids

If your baby is eating solid foods, give them plenty of water or diluted fruit juice. Try to encourage them to eat fruit, which can be puréed or chopped, depending on their ability to chew. The best fruits for babies to eat to treat constipation are:

apples

apricots

grapes

peaches

pears

plums

prunes

raspberries

strawberries

Never force your baby to eat food if they don't want to. If you do, it can turn mealtimes into a battle and your child may start to think of eating as a negative and stressful experience.

If your baby is still constipated after a change in diet, they may have to be prescribed a laxative. Bulk-forming laxatives aren't suitable for babies, so they'll usually be given an osmotic laxative. However, if this doesn't work, they can be prescribed a stimulant laxative.

Children

For children, laxatives are often recommended alongside changes to diet. Osmotic laxatives are usually tried first, followed by a stimulant laxative if necessary.

As well as eating fruit, older children should have a healthy, balanced diet, which also contains vegetables and wholegrain foods, such as wholemeal bread and pasta.

Try to minimise stress or conflict associated with meal times or using the toilet. It's important to be positive and encouraging when it comes to establishing a toilet routine. Allow your child at least 10 minutes on the toilet, to make sure they've passed as many stools as possible.

To encourage a positive toilet routine, try making a diary of your child's bowel movements linked to a reward system. This can help them focus on using the toilet successfully.

Top tips for parents

A diet rich in fibre and with plenty of fluids will help, even if your child is being treated with laxatives.

Children with long-term (chronic) constipation don't usually have anything physically wrong with them. However, it can take time to correct the problem, so be patient.

Encourage your child to have a regular toilet habit and allow them plenty of time.

A reward chart for passing a stool can be useful if your child tends to "hold on".